MECHANICAL PROCESSING OF EUROPEAN GREEN CRAB (CARCINUS MAENAS), THE DEVELOPMENT OF A VALUE-ADDED PRODUCT AND THE USE OF RESTRUCTURING ADDITIVES TO INCREASE THE FUNCTIONAL PROPERTIES OF GREEN CRAB PATTIES

MECHANICAL PROCESSING OF EUROPEAN GREEN CRAB (CARCINUS MAENAS), THE DEVELOPMENT OF A VALUE-ADDED PRODUCT AND THE USE OF RESTRUCTURING ADDITIVES TO INCREASE THE FUNCTIONAL PROPERTIES OF GREEN CRAB PATTIES

By Joseph A. Galetti

Thesis Advisors: Dr. Denise Skonberg and Dr. Beth Calder

A Lay Abstract

in Partial Fulfillment of the Requirements for the

Degree of Master of Science

(in Food Science and Human Nutrition)

December, 2010

The European Green Crab (Carcinus maenas) is an invasive predator which has the potential to be a valuable food source for human consumption. Due to the small size of green crab, hand picking commercial operations are not feasible. The overall objectives of this research were to develop methods to produce and utilize green crab mince.

            The first study evaluated the effects ofthermal processing, crab size and breaker bar setting on the mechanical separator on green crab mince yield and quality. Mechanical processing of green crabs resulted in high mince yield (~49.2 %). Small crabs contained significantly more fat than large crabs. Low values for protein degradation and low aerobic plate count values indicate that green crab mince was of good microbial quality. Overall results indicated that small green crabs which were mechanically processed at a 0.000 breaker bar setting resulted in the highest mince yield and were easiest to process.

            In the second part of this research, empanadas (South American stuffed and fried pastries) containing 30, 50 and 70 % green crab mince by filling weight were developed and rated by consumers for consumer acceptability. Empanadas containing 30 and 50 % mince had significantly higher ratings for filling appearance, flavor and overall acceptability compared to the empanadas with 70 % mince. All of the ratings for the 30 and 50 % empanadas approached ‘like moderately’ which indicates potential for this novel product. A sauce may be beneficial in enhancing the moistness and crab flavor of the empanadas. Many of the panelists would ‘probably or definitely buy’ green crab and vegetable empanadas if they were available to them locally.

            The third part of this research determined how additives used to restructure protein productsaffected the texture, color, cook yield, water-holding capacity and composition of green crab mince patties. The combination of 5 % isolated soy protein and 2 % transglutaminase appeared to change the functional properties of green crab mince patties most significantly based on textural and compositional analyses.

            These results demonstrated a potential use for green crab which may stimulate a new fishery and result in the development of new food products.